202.223.12.0/23

inetnum:        202.223.12.0 - 202.223.15.255
netname:        JCV
descr:          Joetsu Cable Vision Co.,Ltd.
country:        JP
admin-c:        JP00164408
tech-c:         JP00164408
remarks:        This information has been partially mirrored by APNIC from
remarks:        JPNIC. To obtain more specific information, please use the
remarks:        JPNIC WHOIS Gateway at
remarks:        http://www.nic.ad.jp/en/db/whois/en-gateway.html or
remarks:        whois.nic.ad.jp for WHOIS client. (The WHOIS client
remarks:        defaults to Japanese output, use the /e switch for English
remarks:        output)
last-modified:  2019-06-27T23:02:04Z
source:         JPNIC


role:           JCV Network Operation Team
nic-hdl:        JP00164408
address:        Joetsu Cable Vision Co.,Ltd.
address:        2-2-27 Nishishirocho
address:        Joetsu-shi, Niigata
address:        Japan
phone:          +81-25-526-2111
fax-no:         +81-25-524-0453
e-mail:         jcv-ix-isp@jcv.co.jp
notify:         jcv-ix-isp@jcv.co.jp
mnt-by:         MAINT-AS131937
changed:        jcv-ix-isp@jcv.co.jp 20200904
source:         JPIRR

IP address ranges, or netblocks, are groups of related IP addresses. They are usually represented as a base IP address, followed by a slash, and then a netmask which represents how many IP addresses are contained within the netblock. This format is known as CIDR. You'll also sometimes see netblocks given as a start ip address, and an end ip address, or an ip address range.

Traffic works its way around the internet based on the routing table, which contains a list of networks and their associated netblocks.